The present application is directed to apparatus that provide therapeutic treatment of internal pathological conditions using high-intensity focused ultrasound energy, and more particularly, to providing improved apparatus for insertion and deployment of a HIFU therapy transducer, with or without an imaging component.
Delivery of high-intensity focused ultrasound (HIFU) energy has emerged as a precise, non-surgical, minimally-invasive treatment for benign and malignant tumors. (See, e.g., S. Vaezy, M. Andrew, P. Kaczkowski et al., “Image-guided acoustic therapy,” Annu. Rev. Biomed. Eng. 3, 375-90 (2001)). At focal intensities 4-5 orders of magnitude greater than diagnostic ultrasound (typically about 0.1 W/cm2), HIFU (typically about 1000-10,000 W/cm2) can induce lesions or tissue necrosis at a small location deep in tissue while leaving tissue between the ultrasound source and focus unharmed. Tissue necrosis is a result of focal temperatures typically exceeding 70° C. which can occur with relatively short intervals of HIFU exposure. HIFU is currently being used clinically for the treatment of prostate cancer and benign prostatic hyperplasia, as well as malignant bone tumor and soft tissue sarcoma. Clinical trials for HIFU treatment of breast fibroadenomas and various stage 4 primary and metastatic cancer tumors of the kidney and liver are underway.
Uterine fibroid, as an example of a pathological condition in the female pelvis, is the most common pelvic tumor in women of reproductive age. Uterine fibroids, or leiomyoma, are benign tumors that cause abnormal uterine bleeding. The incidence of fibroids has been estimated to be 20-25% in women in their reproductive years, although autopsy studies show an incidence upwards of 75%. Approximately ⅓ of these women will have a tumor that is symptomatic requiring treatment. HIFU energy delivered using a transvaginal transducer can provide a feasibly minimally-invasive treatment for uterine fibroids.
Further development of HIFU devices for providing therapy in obstetrics and gynecology, as well as other fields of medical endeavor, is desired. In particular, improved devices are needed which can provide noninvasive therapeutic treatment of uterine fibroids, recurrent leiomyosarcoma, and other solid tumors of the uterine corpus and cervix, as well as abnormal uterine bleeding conditions and many other obstetric and gynecologic pathological conditions.
A major challenge for transvaginal HIFU treatment of uterine pathologies is the deployment of a HIFU therapy transducer having an aperture of adequate size. In general, devices with a larger HIFU aperture tend to optimize the focal length of the HIFU beam and the therapeutic effect of the focused ultrasound energy. However, the size and configuration of the HIFU aperture are generally limited by the size and shape of the vaginal cavity and the location of the cervix and vaginal fornices.
Even more challenging is the issue of transvaginal insertion of a HIFU therapy transducer through the rather narrow vaginal introitus. The present application addresses the problems of insertion of a probe with a HIFU transducer through small passages, such as the vaginal introitus, and deployment of the HIFU transducer, with or without an imaging component, within a body cavity in order to achieve optimal imaging and HIFU therapeutic effects.